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The hydroformylation of propene to give predominantly iso‐butanal has been achieved; class‐leading selectivity is possible even at higher temperatures that deliver fast conversion. Racemic rhodium complexes of bidentate phospholane phosphites derived from tropos‐biphenols and unusual solvent systems are the key to the selectivity observed. [ABSTRACT FROM AUTHOR]

A new hydrogenation catalyst based on a manganese complex of a chiral P,N,N ligand has been found to be especially active for the hydrogenation of esters down to 0.1 mol % catalyst loading, and gives up to 97 % ee in the hydrogenation of pro-chiral deactivated ketones at 30-50 °C. [ABSTRACT FROM AUTHOR]

This account describes studies on the catalytic hydrogenation of carbonyl groups that are not readily reduced. The development of well-defined chiral phosphine-diamine ruthenium catalysts for hydrogenation of ketones and esters is described. These chiral catalysts promote the hydrogenation of ketones functionalised with tertiary alkyl and gem-dimethyl groups with enantioselectivities of up to 98% ee. They also reduce a range of heterocyclic and nitrilefunctionalised ketones that react slowly with or inhibit other catalysts. Changing from ruthenium to iridium complexes gives highly selective catalysts that also hydrogenate (the more reactive) secondary alkyl functionalised ketones, including those with unprotected amines. These catalysts operate rapidly at room temperature, require low catalysts loadings, and deliver up to 98% ee. Achiral variants of these catalysts also promote the hydrogenation of esters under mild conditions. This account also describes our studies that shed light on the mechanism of action of these catalysts, and a stereochemical model is proposed. [ABSTRACT FROM AUTHOR]

Enantioselective transfer hydrogenation of benzofuranyl aryl ketones proceeds with moderate to good enantioselectivity even when the aryl group is not sterically differentiated by ortho-substituents. The best results are obtained with substrates that are functionalised by electron-withdrawing aryl groups that contrast with the electron-rich benzofuran, which is consistent with [Ru-ArC-H]˙Ar π interactions acting as a control element. Enantioselective pressure hydrogenation gives lower enantioselectivity irrespective of electronic effects, unless the aryl group is ortho-substituted, in which case up to 86% ee can be realised. [ABSTRACT FROM AUTHOR]

Using the phospholane-phosphite ligand, BOBPHOS, almost perfect regioselectivities and high enantioselectivities (up to 92% ee) are observed in Rh catalysed enantioselective hydroformylation of vinyl arenes. This can be achieved under solvent-free conditions. [ABSTRACT FROM AUTHOR]

Using a family of novel mononuclear and dinuclear palladium complexes of phanephos ligands, the simultaneous control of regioselectivity and enantioselectivity in the hydroxycarbonylation and alkoxycarbonylation of styrene derivatives has been realised for the first time. [ABSTRACT FROM AUTHOR]